Great Lakes fish

Lake Superior State University researchers have determined that Atlantic salmon are naturally reproducing in the St. Mary's River.

The prized game fish were originally native to Lake Ontario, but experienced a massive population decline by the late 1800's. Today, Atlantic salmon are stocked in the St. Mary's River and in other parts of the upper Great Lakes.

Though the Atlantic salmon population remained healthy when maintained by the St. Mary's fishery, the salmon population did not take root naturally, apparently due to a thiamine deficiency.

While conducting research for his senior undergraduate thesis on sturgeon, Stefan Tucker found what he suspected were Atlantic salmon fry in the St. Mary's River. His identification was later confirmed by University of Michigan taxonomist Gerald Smith. Tucker and a team of researchers concluded that the Atlantic salmon population is indeed naturally reproducing.

The discovery is not only exciting for those at LSSU, the Michigan Dept. of Natural Resources, and others who have been involved with stocking Atlantic salmon in the upper Great Lakes for more than two decades, but also to anyone who follows the changing dynamics of the Great Lakes, especially in relation to lake trout and salmonids.

Though this discovery answers one question, it begs others.

Tucker concluded his thesis by stating that "the extent of natural reproduction and mechanisms influencing reproductive success are unclear and warrant further attention."

This Saturday, 35 baby sturgeon will be released into the Kalamazoo River at a sturgeon release party. It’ll be in New Richmond and it’s open to the public.

Lake sturgeon are ancient fish. They’re Michigan’s oldest and biggest fish species and can live to be more than 100 years old. Many populations of lake sturgeon in the Great Lakes were wiped out decades ago, but people have been working to bring them back.

​Environmental groups are asking the state to take back permission for a fish hatchery to expand its operations on a legendary trout stream. The operator has been given permission to raise as much as 300,000 pounds of rainbow trout in the facility.

The complaint says there are not enough protections to ensure the Grayling Fish Hatchery won’t allow diseases and parasites to escape into the Au Sable River.

Marvin Roberson is with the Sierra Club.

“The permit doesn’t require those pools to be monitored to see whether or not fish or parasites or diseases are escaping from the facility, and we think it’s outlandish to say 'you don’t have to check to see whether those things are getting out,'” Roberson said.

A spokesman for the state Department of Environmental Quality says the agency is closely monitoring the water around the hatchery, and will act quickly if there’s a problem.

You’ve probably heard about the big bad invasive silver or bighead carp, also known as Asian carp.

But there’s another invasive fish that’s roughly a third the size of the carp that’s already done a lot of damage to Great Lakes fisheries. Alewives have been a particular menace in Lakes Michigan and Huron. The invasive fish cause all kinds of problems for native lake trout.

Alewives scarf down lake trout eggs and very young fish. But even once lake trout grow big enough to turn the tables and eat the alewives, the invasive fish still cause problems.

TRAVERSE CITY – Many fish markets in the Great Lakes region are running short of whitefish, and it's coming at a bad time: the Passover holiday.

Whitefish is a key ingredient in gefilte fish, a traditional Jewish dish that originates in eastern Europe. Recipes vary, but it often consists of ground fish, vegetables such as onion and carrots, and bread crumbs formed into loaves or balls.

The shortfall results partly from the bitterly cold winter that caused vast sections of the Great Lakes to freeze over. The ice cover kept some commercial fishing crews stuck in port. A drop in the whitefish population is also to blame.

Kevin Dean of Superior Fish Co. near Detroit says his latest shipment amounted to just 75 pounds, although he requested 500 pounds.

PORT CLINTON, Ohio (AP) - Ohio's wildlife agency is looking at bringing a prehistoric fish back to Lake Erie. The Ohio Department of Natural Resources is looking into whether it can reintroduce breeding populations of sturgeon to the lake.

Sturgeon were once plentiful but thought to be all but gone from Lake Erie less than two decades ago.

Twice in early 2012, Zhang crossed the Ambassador Bridge connecting Detroit and Windsor, Ontario, with a truckload of fish from Arkansas. The fish were packed in ice, and included two species of Asian carp.

Scientists say the largest of the Great Lakes is heating up faster than any other lake on Earth.

What's behind the warming? And could this be good news for those who enjoy Great Lakes fishing?

Tim Cline is a PhD student at the University of Washington's School of Aquatic and Fishery Sciences. He has studied the effect of temperature on fish in Lake Superior, and he joined us today to discuss the issue.

He also spoke about how, unlike the other four Great Lakes, Lake Erie is surrounded by agriculture and a more urbanized landscape.

You can listen to him speak about his "50 and 2 Rule" here:

Lake Erie has seen a resurgence in blooms of cyanobacteria (sometimes referred to as blue-green algae) over the last ten years. It was once a big problem in the 60s and 70s, and it has returned as a problem again.

We kick off our week-long series In Warm Water: Fish and the Changing Great Lakes with a look at Lake Superior.

It has long been the coldest and most pristine Great Lake. Its frigid waters have helped defend it from some invasive species that have plagued the other Great Lakes. But Lake Superior’s future could look radically different. Warming water and decreasing ice are threatening the habitat of some of the lake’s most iconic fish.

It looks like food for salmon will continue to be scarce in Lake Michigan. Researchers say it appears not many alewives were born in the lake this year - and salmon eat almost nothing else.

Neither salmon nor alewives are native to the Great Lakes, but it's bad news for people trying to keep the billion-dollar sport fishery alive in Lake Michigan.

Peter Payette is with our partners at Interlochen Public Radio and he's been covering this story. He explains that every year researchers go out on the lakes to see what’s happening.

"One of the important surveys is of prey fish, the little feeder fish that big fish like salmon like to eat, and in Lake Michigan this year they found very few newborn alewives. There are alewives in the lake, ones that were born in years past. But the young of the year, the new class of alewives; they found very few," he says.

The sea lamprey is an invasive fish with a round mouth like a suction cup. It latches onto big fish like lake trout and salmon, drills its razor sharp tongue into them, and gets fat drinking their blood and body fluids. A single lamprey can kill up to 40 pounds of fish in its lifetime.

Scientists spend a lot of time trying to outsmart them, and they’ve just made a new discovery.

When you’re a male sea lamprey, with that slimy skin, and a suction cup full of teeth for a face: you’ve got to compensate for that somehow.

Hey baby, is it hot in here? Or is it just me?

It turns out male sea lampreys are hot. They grow a swollen ridge on their back when they’re sexually mature. Scientists at Michigan State University have discovered that ridge heats up when males get around a lady lamprey.

It’s near the end of spawning season for Michigan’s oldest and biggest fish species, the lake sturgeon. Overfishing and hydraulic dams built to power industry have wiped out many lake sturgeon populations in the Great Lakes.

A group of people and government agencies are trying to increase the odds the kind of sturgeon specific to the Kalamazoo River will survive.

Sturgeon have been around since the age of dinosaurs. So they’re a lot different from other fish in the Great Lakes. They don’t have a normal skeleton. Instead, they’ve got these bony plates on the outside of their bodies, called scutes. They have no fish scales.